[Infection of tupaia hepatocytes with hepatitis C virus in vitro].

OBJECTIVE: Tupaia belangeri (tree shrew) has a close phylogenetic relationship with primates and has been shown to be susceptible to a variety of human viruses. This study was conducted to investigate whether or not hepatitis C virus (HCV) could infect primary tupaia hepatocytes (PTHs) in vitro. METHODS: Serum-derived HCV was cultivated with PTHs, and then positive and negative strand HCV RNA in PTHs, as well as the encapsidated HCV RNA in the culture medium were detected to evaluate the infection. Virus from the culture medium of the infected PTHs was passed to naïve PTHs, and the quasispecies of HCV were compared among the inoculum and PTHs after infection and passage. RESULTS: Both positive and negative strand HCV RNA were detected in PTHs after infection. The negative strand RNA was detectable from day 5 to day 10 after infection, while the positive strand RNA was positive up to day 14. HCV RNA, which was RNase resistant, could be detected from the culture medium of the infected PTHs from day 3 to day 14. Production of infectious virons of PTH were demonstrated by passage HCV to naïve PTHs. Compared analysis of HCV quasispecies after infection and passage showed that PTHs were selectively infected with defined HCV quasispecies, and new quasispecies emerged in PTHs after passage. CONCLUSION: The present study strongly indicates that PTHs could be infected by HCV and support HCV replication in vitro. Our results would be helpful for the establishment of a tupaia model of HCV infection.

[Hfgl2/fibroleukin expression in liver and peripheral blood mononuclear cells (PBMC) and its correlation with disease severity].

OBJECTIVE: Viral hepatitis remains a major public health problem and the most common type of liver disease worldwide. There are an increasing number of patients with chronic hepatitis B who develop acute hepatitis on chronic condition (AOC) and die of acute hepatic failure both as a result of lack of understanding of the pathogenesis of the disease and lack of effective treatment. The hallmark of AOC is the extreme rapidity of the necromicroinflammatory process resulting in widespread or total hepatocellular necrosis in weeks or even days. Our previous studies have shown in an experimental animal model of fulminant viral hepatitis caused by murine hepatitis virus strain 3, the importance of macrophage activation, and expression of a unique gene mfgl 2 which encodes a serine protease capable of directly cleaving prothrombin to thrombin, resulting in widespread fibrin deposition within the liver and hepatocyte necrosis. The undergoing study in this report is designed to identify the role of hfgl 2 (human fibrinogen like protein 2) /fibroleukin in patients with viral hepatitis. METHODS: Liver tissues were obtained from 23 patients with AOC hepatitis B, and from 13 patients with inactive chronic hepatitis B (CHB) and 14 patients with chronic hepatitis B with cirrhosis during the year of 1995 to the end of 2001. Liver biopsies were performed within 30 min after the patients were diagnosed with death as a result of acute hepatic failure. Liver samples were also obtained from 4 liver donors as normal controls. In addition, peripheral blood mononuclear cells (PBMC) were isolated from 30 patients (unpaired) with AOC hepatitis B and 10 patients with CHB during the May of 2001 to March of 2002 and 10 healthy volunteer as negative control. PBMCs were freshly isolated and smeared on slides and kept at -80 degree C for further use. Histological sections were stained with hemotoxylin and eosin. A 169 bp of hfgl 2 cDNA probe and a polyclonal or monoclonal antibody against hfgl 2 were used to detect the expression of hfgl 2 mRNA and protein in liver samples as well as PBMC by immune histochemistry separately. RESULTS: Liver tissues from the patients with acute on chronic hepatitis had classical pathological features of acute necroinflammation. Hfgl 2 was detected by immune histochemistry in 21 of 23 patients (91.3%) in liver sections from patients with acute on CHB, while only 1 of 13 patients (7.7%) with CHB and cirrhosis and no evidence of active disease had hfgl 2 mRNA or protein expression. 28 of 30 patients (93.3%) with acute on CHB and 1 of 10 with CHB were detected with hfgl 2 expression in PBMC. There was no hfgl 2 expression in either the liver tissue or the PBMC from the normal donors. There was positive correlation of hfgl 2 expression and the severity of the disease displayed by the value of bilirubin and PT. CONCLUSION: The molecular and cellular results reported here in patients with acute on chronic hepatitis and who died of acute hepatic failure correlates with previous report in 8 patients with fulminant hepatic failure (FHF) and mimic closely the changes observed in the murine model of fulminant viral hepatitis in which the pathogenesis of the disease has been studied in a stepwise fashion. This study further suggests that virus induced hfgl 2 prothrombinase/fibroleukin expression and the potent function of the protein it encodes plays a pivotal role in initiating acute severe hepatitis on the baseline of chronic hepatitis. The measurement of hfgl 2/fibroleukin expression in PBMC may serve as a useful marker to monitor the severity of disease in patients with the AOC hepatitis B and a target for therapeutic intervention.

Lethiferous effects of a recombinant vector carrying thymidine kinase suicide gene on 2.2.15 cells via a self-modulating mechanism.

AIM: To determine the lethiferous effects of a recombinant vector carrying thymidine kinase (TK) suicide gene on 2.2.15 cells and the possible self-modulating mechanism. METHODS: A self-modulated expressive plasmid pcDNA3-SCITK was constructed by inserting the fragments carrying hepatitis B virus antisense-S (HBV-anti-S) gene, hepatitis C virus core (HCV-C) gene, internal ribosome entry site (IRES) element of HCV and TK gene into the eukaryotic vector pcDNA3, in which the expression of TK suicide gene was controlled by the HBV S gene transcription. 2.2.15 cells that carry the full HBV genome and stably express series of HBV antigen were transfected with pcDNA3-SCITK or vector pcDNA3-SCI which was used as the mock plasmid. The HepG2 cells transfected with pcDNA3-SCITK were functioned as the negative control. All the transfected cells were incubated in DMEM medium supplemented with 10 microg/ml. of ganciclovir (GCV). The HBsAg levels in the supernatant of cell culture were detected by ELISA on the 1st, 3rd and 6th day post-transfection. Meanwhile, the morphology of transfected cells was recorded by the photograph and the survival cell ratio was assessed by the trypan blue exclusion test on the 6th day post-transfection. RESULTS: The structural accuracy of pcDNA3-SCITK was confirmed by restriction endonuclease digestion, PCR with specific primers and DNA sequencing. The HBsAg levels in the supernatant of transfected 2.2.15 cell culture were significantly decreased on the 6th day post-transfection as compared with that of the mock control (P<0.05). The lethiferous effect of pcDNA3-SCITK expression on 2.2.15 cells was initially noted on the 3rd day after transfection and aggravated on the 6th day post transfection, in which the majority of transfected 2.2.15 cells were observed shrunken, round in shape and even dead. With assessment by the trypan blue exclusion test, the survival cell ratio on the 6th day post transfection was 95% in the negative control and only 11% in the experimental group. CONCLUSION: The results indicate that suicide gene expression of pcDNA3-SCITK can only respond to HBV-S gene transcription, which may be potentially useful in the treatment of HBV infection and its related liver malignancies.

[Clinical study of anti-hepatic fibrosis effect of IFN-gamma in patients with chronic hepatitis B].

OBJECTIVE: This was an open, random, control and multicenter clinical trial. In the study, the anti-hepatic fibrosis effect of rhIFN-gamma and its side reactions were evaluated. METHODS: A total of 289 patients enrolled in clinical trial, 153 patients in trial group and 136 patients in control group. The routine strategy is given in all patients. In addition, every patient in trial group received rhIFN-gamma at a dose of 1 MU intramuscularly daily for the first three months and 1 MU every other day for the following six months. Patients of two groups were followed up for another three months after the treatment. Histological indices, serum hepatic fibrosis indices, ultrasound B and symptoms and signs evaluated the effect. For patients who accepted two liver biopsies before and after treatment, the effect was determined by semiquantitative score system while for patients who did not accepted liver biopsy, serum hepatic fibrosis indices and ultrasound B were major criteria. RESULTS: The efficient of treatment were 66% in trial group vs. 16.2% in control group and the obviously efficient of treatment was 27.8% in trial group vs. 7.4% in control group (P < 0.001). For patients who accepted two liver biopsies before and after treatment, the efficient of treatment was 63% in trial group vs. 24.1% in control group and the obviously efficient of treatment was 27.8% in trial group vs. 13.8%. For patients who did not accepted liver biopsy, the efficient of treatment was 67.7% in trial group vs. 14.0% in control group and the obviously efficient of treatment was 22.2% in trial group vs. 5.6%. None of patients emerged serious side reactions during clinical trial. CONCLUSION: The results confirmed that rhIFN-gamma have a better anti-hepatic fibrosis effect to patients with chronic hepatitis B.

[Expression of human fibroleukin gene acute on chronic hepatitis B and its clinical significance].

OBJECTIVE: To investigate the mRNA and protein expressions of human fibroleukin gene (hfg12) in acute on chronic (AOC) hepatitis B and its clinical significance. METHODS: Liver tissues were obtained from 23 patients with AOC hepatitis B, 13 patients with chronic hepatitis, and 14 patients with cirrhosis to be examined histologically. Immunohistochemistry and in situ hybridization were used to detect the mRNA and protein expressions of hfg12 in the liver tissues. Double staining was used to the hfg12 positive samples to examine both the hfg12 and fibrin. Four specimens of liver tissue from normal donors were used as controls. RESULTS: Immunohistochemistry showed that hfg12 was expressed in the liver tissues of 21 out of the 23 patients with AOC hepatitis B (91.30%) and only one out of the 13 patients with chronic hepatitis (7.69%). In situ hybridization showed that hfg12 was expressed in the liver tissues of 13 out of he 23 patients with AOC hepatitis B and in none of the 27 patients with chronic hepatitis or cirrhosis. In patients with AOC hepatitis Kupffer's cell, CD68 positive, was numerous and big, mainly distributed in the necrosis areas. It was identified as the same of hfg12-expressing cells. CONCLUSION: High expression of hfg12 is one of the molecular mechanisms of necrosis of liver cells in AOC hepatitis.

FADD and TRADD expression and apoptosis in primary hepatocellular carcinoma.

AIM:To investigate the clinical features of FADD and TRADD expressions in primary hepatocellular carcinoma (HCC) and to determine their relationship with hepatic apoptosis.METHODS:FADD and TRADD expressions were detected by immunohis-tochemistry and hepatic apoptosis were determined by in situ end-labeling (ISEL).RESULTS:Ten (25.6%) cases of HCC were detected to express FADD protein. The positive rate in HCC is lower than that in non-cancerous adjacent liver tissues (62.5%) (P < 0.05). In those of grade I-II, 8(38.1%) cases were FADD positive, while only 2/18 (11.1%) cases of grade III-had detectable FADD protein (P < 0.05). No relationship was found between FADD expression and other clinical features, such as gender, age, tumor size, different-tiation or metastasis. ISEL positive cells can be seen in all cases of HCC. The hepatic apoptosis was associated with FADD expression as more apoptotic cells were detected in those cases which had moderately to strongly positive FADD, as compared with negative or weak positive FADD cases (P < 0.05). No relationship was found between FADD expression and hepatic apoptosis in non cancerous adjacent liver tissues. Fifteen of 39 (38.5%) cases of HCC were found positive for TRADD prote-in, and similar positive rate (37.5%) in non-cancerous adjacent liver tissues (P > 0.05). The expression of TRADD is correlated with HCC differentiation, as only 22.2% of moderately to highly differentiated HCC showed positive TRADD protein, while as high as 52.4% of poorly differentiated HCC had TRADD (P < 0.05). No relationship was found between TRADD expression and gender, age, tumor size or grade or metastasis, although 42.9% of HCC of grade I/II showed positive TRADD which was slightly higher than that of grade III/IV (33.3%,P>0.05). Hepatic apoptosis was not related to TRADD expression in HCC or non-cancerous adjacent liver tissues.CONCLUSION:Loss of FADD expression plays an important role in HCC carcinogenesis, and expression of TRADD also contributes to HCC development. The cell apoptosis in HCC is associated with FADD expression. However, the expression of TRADD does not correlate well with hepatic apoptosis in HCC.

Analysis of in vivo patterns of caspase 3 gene expression in primary hepatocellular carcinoma and its relationship to p21(WAF1) expression and hepatic apoptosis.

AIM:To detect the expression of caspase 3 gene in primary human hepatocellular carcinoma (HCC) and investigate its relationship top21(WAF1) gene expression and HCC apoptosis.METHODS:In situ hybridization was employed to determine caspase 3 and p21(WAF1) expression in HCC.In situ end-labeling was used to detect hepatocytic apoptosis in HCC.RESULTS:Twenty-one of 39 (53.8%) cases of HCC were found to express caspase 3 transcripts, while 46.2% of HCC failed to express caspase 3.Non-cancerous adjacent liver tissues showed more positive caspase 3(87.5%, 7/8) as compared with HCC (p < 0.05). The expression of caspase 3 is correlated with HCC differentiation, 72.2% (13/18) of moderately to highly differentiated HCC showed caspase 3 transcripts positive, while only 38.1% of poorly differentiated HCC harbored caspase 3 transcripts (italic>p < 0.05). No relationship was found between caspase 3 expression and tumor size or grade or metastasis, although 62.5% (5/8) of HCC with metastasis were caspase 3 positive and a little higher than that with no metastasis (51.6%, p> 0.05). Expression of caspase 3 alone did not affect the apoptosis index (AI) of HCC. The AI was 7.12 in caspase 3 positive tumors (n = 21), while in caspase 3-negative cases (n = 18) 6.59 (italic>p > 0.05). Expression of caspase 3 clearly segregated with p21(WAF1) positive tumors as compared with p21(WAF1) negative cases (16 of 23, 69.6% versus 5 of 16, 31.3%) with statistical significance (p = 0.017).In the cases with positive caspase 3 and negative p21(WAF1), the AI was found slightly higher, but with no statistical significance, than that with expres-sion of p21(WAF1) and caspase 3 (7.21 vs 6.98 , p>0.05).CONCLUSION:Loss of caspase 3 expression may contribute to HCC carcinogenesis, although the expression of caspase 3 does not correlate well with cell apoptosis in HCC.p21(WAF1) may be merely one of the inhibitors which can reduce caspase 3 mediated cell apoptosis in HCCs.

Hepatitis C virus may infect extrahepatic tissues in patients with hepatitis C.

AIM:To explore the status of extrahepatic hepatitis C virus (HCV) infection and replication in hepatitis C patients,and its potential implication in HCV infection and pathogenicity.METHODS:By reverse-transcriptase poly-merase chain reaction (RT-PCR),in situ hybridization (ISH) and immunohis-tochemistry, HCV RNA, HCV replicative intermediate (minus-strand of HCV RNA), and HCV antigens were detected in 38 autopsy extrahepatic tissue specimens (including 9 kidneys, 9 hearts, 9 pancreas, 5 intestines, 2 adrenal glands, 2 spleens, 1 lymph node, and 1 gallbladder) from 9 hepatitis C patients, respectively; and the status of HCV replication in extrahepatic tissues was studied.RESULTS:By RT-PCR, all 9 patients were positive for HCV RNA in kidney, heart, pancreas, and intestine, but only 6(66.7%) patients were positive for HCV replicative intermediate. HCV RNA and HCV antigens were detected in kidney, heart, pancreas, intestine, adrenal gland, lymph node, and gallbladder in 5(55.6%) and 6(66.7%) patients by ISH and immuno-histochemistry, respectively. HCV RNA and HCV antigens were not detected in these extrahepatic organs in 3(33.3%) patients, although their livers were positive for HCV.HCV replicative intermediate detected by RT-PCR was consistent with HCV RNA and HCV antigens detected by ISH and immunohistochemistry (Kappa =0.42-0.75). HCV RNA and HCV antigens were detected in myocardial cells, epithelial cells of intestinal gladular, interstitial cells of kidney, epithelial cells of tubules and glomerulus, pancreas acinar cells and epithelial cells of pancreatic duct, epithelial cells of mucous membrane sinus of gallbladder, cortex and medulla cells in adrenal gland,and mononuclear cells in lymph node. HCV RNA was also detected in bile duct epithelial cells, sinusoidal cells, and mononuclear cells in liver tissues by ISH.CONCLUSION:HCV can infect extrahepatic tissues, and many various tissue cells may support HCV replication; extrahepatic HCV infection and replication may be of concomitant state in most of patients with hepatitis C. The infected extrahepatic tissues might act as a reservoir for HCV, and play a role in both HCV persistence and reactivation of infection. HCV as an etiologic agent replicating and expressing viral proteins in extrahepatic tissues itself contributes to extrahepatic syndrome associated-HCV infection in a few patients with chronic HCV infection.